Mass and count nouns show distinct EEG cortical processes during an explicit semantic task

Tapping the time course of their processing seems a good way to distinguish the categories of mass and count nouns. In fact, since these noun categories designate most of the known world, they are likely to overlap quite extensively in brain space. The lack of clear double dissociations between the two categories in lesion studies,despite extensive investigations (Semenza, Mondini, & Cappelletti,1997; Semenza, Mondini, & Marinelli, 2000), seems indeed to support this hypothesis. Only one ERP study, however, has been so farpublished on this topic. Steinhauer, Roumyana, Newman, Gennari,and Ullman (2001) have demonstrated that count (vs. mass) nouns elicit a frontal negativity which is independent of the N400 marker for conceptual-semantic processing, but resembles anterior negativities related to grammatical processing. No electrophysiological data are available about the mass/count distinction at the lexical-semantic level. The present study investigates the effects of a semantic categorization task.